But she said after her practice run in Spain on Friday: "I am in no way bitter about what has happened recently.

"Yes I was disappointed but this is a tough environment. The best drivers are fighting to get in here.

"We all bring something different to the table and we are all fighting for the same opportunities and there are so few opportunities. I was well aware it was going to be a tough fight and it is."

Sutil was appointed as reserve driver ahead of Wolff in the wake of race driver Valtteri Bottas suffering a back injury that forced him to miss the season-opening Australian Grand Prix.

Williams said one of the reasons was that Wolff does not possess a 'super-licence' - the licence required to compete in F1 races.

"I will get a super-licence when I need one. Right now, there is no reason," said Wolff.

"I can't apply for a super-licence in the hope I will do a race until I see that a race is close to happening, which right now it is not. What do I need it for? Right now, I don't need it."

Female drivers in F1

Maria Teresa de Filippis - 5 races (1958-69), 3 starts - 0 points

Lella Lombardi - 17 races (1974-76), 12 starts - 0.5 points

Divina Galica - 3 races (1976 & 78), 0 starts (did not qualify)

Desire Wilson - 1 race (1980), 0 starts (did not qualify)

Giovanna Amati - 3 races (1992), 0 starts (did not qualify)

Her next outing in the car will be in a test at the Red Bull Ring a couple of days after the Austrian Grand Prix next month.

She will then run in first practice at the British Grand Prix on 3 July.

Wolff said she would not start to think about talking to Williams about their plans for 2016 until after her run at Silverstone.

"My frame of mind is to optimise every time I'm in the car, to learn as much as I can, to make sure I am always improving, doing what the team expect, and then see where that brings me, because it's very difficult in this environment," said Wolff, adding that she had lost 0.3 seconds on her fastest lap on Friday after a "moment" in Turn Three

"I am not someone who lets my head get down. Things can change very quickly. I am completely realistic.

"I am close but I am very far away, I know that. Ultimately I was just so looking forward to being in the car this morning, because that is the best part and it speaks more than 1,000 words can."

Wolff will test again in Austria in June ahead of another practice appearance at the British GP on 3 July